title: Dronedarone versus amiodarone in preventing premature ventricular contractions in an in vitro model of "border zone".
abstract: OBJECTIVE
  To compare the acute ability of amiodarone and dronedarone (a noniodinated benzofuran derivative with a pharmacologic profile similar to amiodarone) to prevent premature ventricular contractions (PVCs) occurrence.
  
  
  METHODS
  We used an in vitro model of rabbit right ventricle mimicking the "border zone" existing between normal and ischemic/reperfused regions to test acute electrophysiological effects of dronedarone and amiodarone both at 1 and 10 μmol/L.
  
  
  RESULTS
  Similar to amiodarone, dronedarone affected action potential parameters with multichannel blocking properties. Dronedarone at both concentrations was equivalent to amiodarone regarding PVCs occurrence, except regarding extrasystoles occurrence during the reperfusion period (dronedarone, 10 μmol/L, was superior to amiodarone with extrasystoles incidence at 33% and 50%, respectively vs. 92% in controls, P < 0.05). Both dronedarone and amiodarone systematically induced conduction blocks during simulated ischemia (in 100% of preparations vs. 42% in controls, P < 0.05) and a marked decrease of Vmax (to 24 and 23 V/s at 10 minutes of ischemia with 1 and 10 μmol/L dronedarone versus 65 V/s in controls, P < 0.05), thus indicating class 1 antiarrhythmic effects. Both dronedarone and amiodarone at 10 μmol/L induced an increase of APD90 dispersion between normal and ischemic regions, without pro-arrhythmic effects.
  
  
  CONCLUSIONS
  Dronedarone and amiodarone have very similar electrophysiological effects in this in vitro model of border zone and were both efficient in preventing PVCs occurrence particularly through a class 1 antiarrhythmic effect.
authors.affiliation: *Department of Cardiology, CHU de Caen, Caen, France; †EA 4650 Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, Normandie Université, Caen, France; and ‡Department of Cardiovascular Sciences, Sapienza University of Rome, Rome, Italy.
authors.forename: Joachim
authors.initials: J
authors.lastname: Alexandre
authors.forename: René
authors.initials: R
authors.lastname: Rouet
authors.forename: Paolo-Emilio
authors.initials: PE
authors.lastname: Puddu
authors.forename: Farzin
authors.initials: F
authors.lastname: Beygui
authors.forename: Alain
authors.initials: A
authors.lastname: Manrique
authors.forename: Paul
authors.initials: P
authors.lastname: Milliez
mesh_terms: D000638:Amiodarone / Q000031:analogs & derivatives* / Q000494:pharmacology*; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D000077764:Dronedarone; D004562:Electrocardiography; D006321:Heart / Q000187:drug effects; D006327:Heart Block; D006329:Heart Conduction System / Q000187:drug effects; D006352:Heart Ventricles / Q000187:drug effects; D066298:In Vitro Techniques; D015428:Myocardial Reperfusion Injury / Q000503:physiopathology / Q000517:prevention & control; D011817:Rabbits; D012996:Solutions; D018879:Ventricular Premature Complexes / Q000503:physiopathology / Q000517:prevention & control*
chemical_list: D000889:Anti-Arrhythmia Agents; D012996:Solutions; D000077764:Dronedarone; D000638:Amiodarone